{  Statement: http://acmp.ru/?main=task&id_task=439
   Verdict: Accepted
}
uses
    SysUtils, Math;

var
    n,p:double;

begin
reset(input,'input.txt');
rewrite(output,'output.txt');
read(n, p);
p := p / 100;
write((1 / ((1 - p) / n + p)):0:16);
end.